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Heap Sort

Learn how to solve the 'Heap Sort' problem. This detailed resource details brute force and optimized approaches.

Problem Statement

Easy

Write a function heap_sort(arr) that sorts a list of integers arr in ascending order using the Heap Sort algorithm (building a max heap first) and returns the sorted list.

Constraints
  • 0 <= len(arr) <= 10^4
  • -10^5 <= arr[i] <= 10^5

Examples

Example 1
Input
arr = [12, 11, 13, 5, 6, 7]
Output
[5, 6, 7, 11, 12, 13]
Explanation

A max heap is created, the maximum element is repeatedly swapped with the last element of the heap, and heapify is performed.

Need a Hint?
Analyze the input constraints. Try sorting first (O(n log n)) or using a hash map/set to track seen elements in O(n) time.
Edge Cases to Watch
  • Empty list or null input variables
  • Single item lists/arrays
  • Extremely large input bounds causing integer or stack overflow

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